Search for "N4 JLPT Listening 練習." The official workbook comes with one CD (60 minutes). YouTube has hundreds of hours of simulated listening.
Take the first mock test in the workbook without studying. Time yourself strictly. Do not pause the listening section. This will hurt your ego, but it reveals your weakest section (Vocab? Grammar? Reading speed?).
Here is the secret many learners miss: The Koushiki Mondaishuu is available as an official Kindle e-book on Amazon Japan. You can purchase it for about ¥1,500. While it is not a raw PDF, you can read it on the Kindle app (PC, Mac, iOS, Android). This gives you:
To buy it, create an Amazon Japan account and search for: 日本語能力試験 公式問題集 N4 (Amazon Kindle Store).
Official Answer Sheet & Answers
The PDF includes a printable answer sheet and detailed correct answers (no lengthy explanations, though – just the answers).
Portable & Searchable
The PDF version is easy to carry on a tablet or laptop. You can search for specific question types or keywords, which isn’t possible with the physical book.
Low Cost (or Free)
While the physical book costs ~¥1,400, the PDF is often available legally via library services or purchased at a lower price from Japanese e-book stores. Some learners share scanned copies – but beware of copyright issues.
While not official, this site has compiled every known leaked official question from the past decade. It is not a single PDF, but a searchable database.
The real value of the Koushiki Mondaishuu isn't in taking the test—it's in reviewing your mistakes.